Heretofore, several polymeric or oligmeric carbohydrates such as cellulose and starch have been successfully sulfonated by the electrophilic addition thereto of sultones, epoxy-sulfonates and halogen-sulfonates in caustic solutions. Attempts to utilize these techniques to sulfonate a monomeric glucoside molecule such as methyl-.alpha.-D-glucoside resulted in the oligomerization or degradation of the molecule. Moreover, the strong hydrogen bonding of the four hydroxyl groups on the glucoside molecule prevents the nucleophilic substitution of the carbohydrate alcoholate or oxy-anion.
Helferich et al (Glucoside von Oxysulfonsauren Und Oxysulfonsaureenstern, Emulsin XLV, Annalen der Chemie, Vol. 547, pp. 201-215, 1941) succeeded in preparing sodium propyl-.beta.-D-glucoside-.gamma.-sulfonate utilizing a complicated five step procedure involving acetate protection/deprotection to form .gamma.-chloro-propyl-.beta.-D-glucoside from glucose and 1,3-dichloropropane, followed by chlorine displacement by iodine which required a second acetate protection/deprotection step. Finally, the end product was formed by iodine displacement in aqueous sodium sulfite. This complicated multi-step procedure resulted in a low overall yield (.about.43%) and required the use of relatively expensive halogenating materials and involved, tedious purification methods. This procedure suffers from the additional disadvantage in that only the 1-O-substituted glucoside derivatives may be prepared thereby.
Those skilled in the art have labored under the assumption that this and similar expensive, time-consuming and inefficient methods were required to produce sulfonated methyl glucoside derivatives inasmuch as attempts to directly sulfonate the molecule always resulted in oligomerization and decomposition due to the acid sensitive acetal linkages in the glucoside molecule.
It is an object of the present invention to provide a simple, economical and efficient method for preparing sulfonated glucoside derivatives.
It is a further object of the invention to provide novel sulfonated glucoside derivatives useful as ionic-type surfactants.
It is still a further object of the present invention to provide a method for recovering petroleum from subterranean formations utilizing novel sulfonated glucoside derivatives.